EC Declaration of Conformity We GOOD WILL INSTRUMENT CO., LTD.

We

GOOD WILL INSTRUMENT CO., LTD.

(1) No. 95-11, Pao-Chung Rd., Hsin-Tien City, Taipei Hsien, Taiwan

(2) Plot 522, Lorong Perusahaan Baru 3, Prai Industrial Estate, 13600 Prai, Penang, Malaysia declares that the below mentioned product

GFG-8215A, GFG-8216A,GFG-8217A, GFG-8219A, GFG -8250A,GFG -8255 A are herewith confirmed to comply with the requirements set out in the Council Directive on the Approximation of the Law of Member States relating to Electromagnetic Compatibilit y (89/366/EEC, 92/31/EEC, 93/68/EEC) and Low Voltage Equipment Directive (73/23/EEC).

For the evaluation regarding the Electromagnetic Compatibility and Low Voltage Equipment Directive, the following standards were applied:

EN 61326-1: Electrical equipment for measurement, control and laboratory use ––

EMC requirements (1997+A1: 1998) Conducted and Radiated Emissions

EN 55011 Group I class A: 1991

Electrostatic Discharge EN 61000-4-2: 1994 Current Harmonic

EN 61000-3-2: 1995

Radiated Immunity ENV 50140: 1993 Voltage Fluctuation

EN 61000-3-3: 1995

Electrical Fast Transients EN 61000-4-4: 1995 Surge Immunity EN 61000-4-5: 1995 Conducted Susceptibility EN 61000-4-6: 1996

Power Frequency Magnetic field EN 61000-4-8: 1993

Voltage Dips/ Interrupts EN 61000-4-11: 1994

Low Voltage Equipment Directive 73/23/EEC & amended by 93/68/EEC Safety Requirements

EN 61010-1: 1990+A1: 1992+A2: 1995; IEC 61010-1: 1990+A1: 1992+A2: 1995

TABLE OF CONTENTS

1. SAFETY SUMMARY… … … . 1

2. INTRODUCTION… … … 5

3. SPECIFICATION… … … . 7

4. FUNCTION DESCRIPTION.… … … . 13

5. USAGE DESCRIPTION… … … . 17

6. APPLICATION NOTE… … … 23

7. MAINTENANCE… … … 33

1.SAFETY TERMS AND SYMBOLS

Please take a moment to review these safety terms and symbols which may appear in this manual or on Equipment to prevent damage to the Function Generators.

WARNING. Warning statements identify condition or practices that could result in injury or loss of life.

CAUTION. Caution statements identify conditions or practices that could result in damage to this product or other property.

DANGER High Voltage

ATTENTION refer to Manual

Protective Conductor Terminal

(ground) Earth Terminal

Frame or Chassis Terminal

FOR UNITED KINGDOM ONLY

NOTE: This lead/appliance must only be wired by competent persons

WARNING: THIS APPLIANCE MUST BE EARTHED

IMPORTANT: The wires in this lead are coloured in accordance with the following code:

Green/ Yellow: Earth Blue: Neutral Brown: Live(Phase)

As the colours of the wires in main leads may not correspond with the colours marking identified in your plug/appliance, proceed as follows:

The wire which is coloured Green & Yellow must be connected to the Earth terminal marked with the letter E or by the earth symbol or coloured Green or Green & Yellow.

The wire which is coloured Blue must be connected to the

terminal which is marked with the letter N or coloured Blue or Black.

The wire which is coloured Brown must be connected to the terminal marked with the letter L or P or coloured Brown or Red.

If in doubt, consult the instructions provided with the equipment or contact the supplier.

This cable/appliance should be protected by a suitably rated and approved HBC mains fuse : refer to the rating information on the equipment and/or user instructions for details. As a guide, cable

of 0.75mm² should be protected by a 3A or 5A fuse. Larger conductors would normally require 13A types, depending on the connection method used.

Any moulded mains connector that requires removal /replacement must be destroyed by removal of any fuse & fuse carrier and disposed of immediately, as a plug with bared wires is hazardous if a engaged in live socket. Any re-wiring must be carried out in accordance with the information detailed on this label.

2. INTRODUCTION

The Function Generator series are stable low distortion instruments which generate signals in the frequency range up to 5MHz. Typical applications include a wide range of audio response testing applications, vibration testing, servo system evaluation, ultra sound applications, and etc.

These instruments include the following features: logarithmic and linear sweep capabilities, together with a built in frequency counter. The sweep capability simplifies the task of finding resonant points of speakers, filter networks and other networks/structures. An oscilloscope may be connected to this instrument for the response to be displayed. The counter can be switched to measure and display the frequency of an external signal up to 150MHz.

l ADDITIONAL FEATURES

1.Low distortion waveforms (sine, triangular and square) and ramp signal.

2.Signal output in seven decade stages, 0.5Hz to 5MHz for GFG -8250A/8255A, 0.3Hz to 3MHz for GFG-8215A/8216A/8217A/8219A.

3.Adjustable sweep time and sweep width both in linear and logarithmic modes.

4.Duty cycle control with signal inversion capability.

5.External Voltage controlled Frequency (VCF).

6.AM or FM modulation modes with internal or external modulation control.

7.A second output for TTL or adjustable CMOS pulses.

8.50 ohm main signal output with DC offset adjustment and 20dB attenuation capability.

9. Supplied with two BNC test leads and AC power cord set.

l FEATURES COMPARISON TABLE FOR MODELS:

MODEL FEATURE

GFG-8215 A

GFG-8216 A

GFG-8217 A

GFG-8219 A

GFG-8250 A

GFG-825 5A

AM/FM ─ ─ ─ ˇ ─ ˇ

SWEEP ─ ─ ˇ ˇ ─ ˇ

COUNTER ─ ˇ ˇ ˇ ˇ ˇ

GCV Output ─ ─ ─ ˇ ─ ˇ

TTL/CMOS ˇ ˇ ˇ ˇ ˇ ˇ

VCF ˇ ˇ ˇ ˇ ˇ ˇ

Duty Cycle

Control ˇ ˇ ˇ ˇ ˇ ˇ

3. SPECIFICATION

GFG-8215A/8216A/8217A/82 19A

GFG- 8250A/8255AA 1.Main

Frequency Range 0.3Hz∼3MHz(7 Range) 0.5Hz∼5MHz(7 Range) Amplitude ≧10Vpp(into 50Ωload) ≧ 10Vpp(into 50Ωload)

Impedance 50Ω± 10％ 50Ω± 10％

Attenuator -20dB± 1dB× 2 -20dB± 1dB× 2

DC Offset ＜-5V∼＞5V

(into 50Ω load)

＜ -5V∼＞5V (into 50Ωload) Duty Control 80%:20%:80% to 1MHz

Continued variable

80%:20%:80% to 1MHz Continued variable Display

6 digits LED display

*GFG -8215A does not have display.

6 digits LED display

Range Accuracy ± 5%+1Hz(at 3.0 position)

*only for GFG-8215A. ---

2.Sine Wave

Distortion

≦1％,0.3Hz∼200kHz THD≦35dB below fundamental in all range (Specification applied from MAX. to 1/10 level)

≦1％,0.5Hz∼ 100kHz THD≦30dB below fundamental in all range (Specification applied from MAX. to 1/10 level) Flatness ＜0.3dB,0.3Hz∼300kHz

＜0.5dB,300kHz∼3MHz

≦0.3dB,below 500kHz

≦1dB,below 5MHz

3.Triangle Wave

Linear ≧98％,0.3Hz∼ 100kHz

≧95％,100kHz∼3MHz

≧98％,0.5Hz∼100kHz

≧95％,100kHz∼ 5MHz

4.Square Wave

Symmetry ± 2％,0.3Hz∼100kHz ±2％,1Hz∼100kHz Rise or Fall Time ≦100ns at maximum output.

(into 50Ωload)

≦50ns at maximum output

(into 50Ωload)

GFG-

8215A/8216A/8217A/8219A

GFG- 8250A/8255A 5.CMOS Output

Level 4Vpp± 1Vpp∼14.5Vpp

± 0.5Vpp adjustable

4Vpp± 1Vpp∼ 14.5Vpp

±0.5Vpp adjustable

Rise or Fall Time ≦120ns ≦120ns

6.TTL Output

Level ≧3Vpp ≧3Vpp

Fan Out 20 TTL load 20 TTL load

Rise or Fall Time ≦25ns ≦25ns

7.VCF

Input voltage 0V∼10V± 1V(100:1) 0V∼10V± 1V(100:1)

Input Impedance 10kΩ± 10％ 10kΩ± 10％

8.GCV(for GFG-8219A/8255A only)

Output voltage

To set the voltage between 0V∼2V as per different frequency.

To set the voltage between 0V∼2V as per different frequency.

9.Sweep Operation(for GFG-8217A/8219A/8255A only)

Sweep/Manual Switch selector Switch selector

Sweep/Rate 100:1 ratio max. and adjustable 100:1 ratio max. and adjustable Sweep/Time 0.5Sec∼30Sec adjustable 0.5Sec∼30Sec adjustable Sweep/Mode Lin./Log. switch selector Lin./Log. switch selector

10.Amplitude Modulation(for GFG-8219A/8255A only)

Depth 0∼100％ 0∼100％

MOD.Freq. 400Hz(INT),DC∼1MHz(EXT) 400Hz(INT),DC∼1MHz(EXT) Carrier BW 100Hz∼3MHz(-3dB) 100Hz∼5MHz(-3dB)

EXT Sensitivity ≦10Vpp for 100％ modulation ≦10Vpp for 100％ modulation

GFG-

8215A/8216A/8217A/8219A

GFG- 8250A/8255A 11.Frequency Modulation (for GFG-8219A/8255A only)

Deviation 0∼± 5％ 0∼± 5％

MOD.Freq. 400Hz(INT),DC∼20kHz(EXT) 400Hz(INT),DC∼20kHz(EXT) EXT Sensitivity ≦10Vpp for 10％ modulation ≦10Vpp for 10％ modulation

12.Frequency Counter

Int./Ext. Switch selector Switch selector

Range 0.3Hz∼3MHz

(5Hz∼150MHz EXT)

0.5Hz∼5MHz (5Hz∼150MHz EXT) Accuracy time base accuracy± 1count Time base accuracy± 1count Time base ± 20ppm(23℃± 5℃) after

30 minutes warm up

±20ppm(23℃± 5℃) after 30 minutes warm up Resolution

The maximum resolution is

100nHz for 1Hz and 1Hz for 100MHz.

The maximum resolution is 100nHz for 1Hz and 1Hz for 100MHz.

Input Impedance 1MΩ/150pF 1MΩ/150pf

Sensitivity

≦35mVrms(5Hz~100MHz)

≦45mVrms(100MHz~150MHz)

*GFG -8215A does not have Frequency Counter function.

≦35mVrms(5Hz~100MHz)

≦45mVrms(100MHz~150MHz)

13.General

Power Source AC115V, 230V± 15%.50/60Hz AC115V, 230V± 15％.50/60Hz

Operation Environment

Indoor use, altitude up to 2000m.

Ambient Temperature 0℃ to 40℃.

Relative Humidity 80%(Maximum).

Installation category II Pollution Degree 2 Storage temperature

& Humidity

-10℃ to 70℃.

70% (Maximum).

GFG-

8215A/8216A/8217A/8219A

GFG- 8250A/8255A Accessories

GT L-101× 2

*GTL-101× 1 for GFG-8215A.

Instruction manual× 1

GT L-101× 2 Instruction manual× 1 Dimension 251(W)× 91(H)× 291(D) m/m 251(W)× 91(H)× 291(D) m/m

Weigh

Approx. 2.0kgs- GFG-8215A 2.1kgs- GFG-8216A 2.15kgs-GFG-8217A 2.2kgs- GFG-8219A

Approx. 2.3kgs- GFG-8250A 2.4kgs- GFG-8255A

WARNING ? To avoid electrical shock, the power cord protective grounding conductor must be connected to ground.

C AUTION ? To avoid damaging the instrument, do not use it In a place where ambient temperature exceeds 40℃.

CAUTION ? To avoid damaging the instrument, do not input more than DC15V to V.C.F.(V.C.G.).

CAUTION ? To avoid damaging the instrument, do not input more than AC150V to Frequency Counter (for GFG-8216A, GFG-8217A, GFG-8219A, GFG-8250A, and GFG-8255A).

CAUTION ? To avoid damaging the instrument, do not input more than AC10Vpp when proceed EXT modulation operation (for GFG -8219A, GFG-8255 A).

l Fig 4.1 FRONT PANEL

POWER

3 1 ^2a

FUNCTION GENERATOR SWEEP/RATE

MOD/DEPTH

13 5 14

SWEEP ON SWEEP OFF FREQUENCY

LOG LIN SWEEP/TIME

SLOW FAST 0

16 9 15 10

AM FM

ADJ

DUTY

CMOS ADJ TTL

R

CMOS

5V 15V

22

OUTPUT

GFG-8219A

12

11 8

AMPL

-20dB ADJ OFFSET

- + MIN MAX

50

GATE

6

M 0.01

m

k Hz

1

0.1 10

4 2

MOD EXT 1M

MOD ON 100k

GATE 10k

17 ^12a

1k 100 10

-20dB ATT 1

7

l Fig.4-2 REAR PANEL

20 21 23 19

230V 115V INPUTS BEFORE OPENING.

TO AVOID SHOCK, REMOVE

INT EXT

TTL/CMOS OUTPUT

DC 15V MAX INPUT VCF/MOD

OUTPUT GCV COUNTER

MAX CAT INPUT COUNTER

AC 150Vrms

250V

IEC1010 CAT

AC

2 9 W 3 6 V A

115

18 24

T0.16A 250V T0.315A 250V FUSE RATING

W A R N I N G

4. FUNCTION DESCRIPTION

1. Power Switch Connect the AC power, then press power switch.

2. Gate Time Indicator

Press the power switch, Gate time indicator will start to flash (the gate time of internal counter is 0.01 second).

2a. Gate Time Selector

Press this key to change gate time when use external counter mode. The change order is according to 0.01s, 0.1s, 1s,10s cycle by pressing these keys.

3. Over Indicator In the external counter mode, the indicator is illuminated when the output frequency is greater than the range selected.

4. Counter Display Shows the external frequency by 6 × 0.3" green display, and shows the internal frequency by 5 × 0.3 green display.

5. Frequency Indicator

Indicate the current frequency value.

6. Gate Time Indicator

Indicate the current Gate time (external. counter mode use only).

7. Frequency Range Selector

To select the required frequency range by pressing the

relevant push button on the panel as shown in

Table 1 and Table 2.

Table 1(for GFG-8215A/8216A/8217A/8219A)

Push bottom 1 10 100 1k 10k 100k 1M

Frequency Range 0.3Hz

∣ 3Hz

3Hz

∣ 30Hz

30Hz

∣ 300Hz

300Hz

∣ 3kHz

3kHz

∣ 30kHz

30kHz

∣ 300kHz

300kHz

∣ 3MHz Table 2(for GFG-8250A/8255A)

Push bottom 1 10 100 1k 10k 100k 1M

Frequency Range 0.5Hz

∣ 5Hz

5Hz

∣ 50Hz

50Hz

∣ 500Hz

500Hz

∣ 5kHz

5kHz

∣ 50kHz

50kHz

∣ 500kHz

500kHz

∣ 5MHz 8. Function Selector Press one of the three push buttons to select the desired

output waveform.

9. Duty Function Pull out and rotate the knob to adjust the duty cycle of the waveform.

10. TTL/CMOS Selector When push in the knob, the BNC terminal of ²⁰ will output a TTL compatible waveform. If pull out and rotate the knob can adjust the CMOS compatible output (5-15Vpp) from the output of BNC ²⁰ .

11. DC Offset Control Pull out the knob to select any DC level of the waveform between ±10V, turn clockwise to set a positive DC level waveform and invert for a negative DC level waveform.

12. Output Amplitude Control with A ttenuation Operation

Turn clockwise for MAX. output and invert for a –20dB output. Pull the knob out for an additional 20dB output attenuation.

12a. 20dB Attenuation Press the knob to adjust a –20dB output.

13 MANU/SWEEP Selector and Frequency Adjustment (Sweep On/Off)

Press and turn clockwise the knob for MAX frequency and invert for MIN frequency. (Keep the pointer within the scale range on the panel.).

Pull out the knob to start the auto sweep operation; the upper frequency limit is determined by the knob position.

14 Sweep Time Control and LIN/LOG Selector

(1) Rotate the knob clockwise to adjust sweep time for MAX, or invert for MIN.

(2) To proceed Linear sweep mode by pushing in the knob, or select LOG sweep mode by pulling out the knob.

15. Control MOD ON/OFF Selector

Pull out the knob, the output can be modulated by internal 400Hz Sine wave or an external signal via CVF/MOD in connector ²¹ .

16. Sweep Width &

Modulation Carrier &AM/FM Selector &FM Selector

(1) Sweep width can be controlled from 0 to 1000 times.

(2) To adjust modulation ratio by turning the knob clockwise for MAX, or invert for MIN.

(3) Press the knob to get AM function or pull it out for FM function.

17 INT/EXT MOD Selector

When press the button once, the indicator will lighten, then the EXT MOD has been selected. Press the key again, the indicator will be off, then INT MOD has been selected.

18. INT/EXT Counter Selector

Select internal counter mode (count the frequency of

model) or select EXT counter mode for an independent

counter (input signal from BNC ¹⁹ ).

19. EXT. Counter Input Terminal

Accepts external signals for measurement.

20. TTL/CMOS Output Terminal

TTL/CMOS compatible signal output

21. VCF/MOD Input Terminal

Used to connect the input voltage required to perform the “voltage control frequency” operation or the EXT modulation operation.

22. Main Output Terminal

Main signal output.

23. GCV Output This is DC voltage output and its voltage amount will follow the change of Frequency.

24. Power Switch 115V and 230V selectable.

l Remark:

(1) The functions of item 2, 2a, 3, 4, 5, 6, 14, 15, 16, 17, 19 and 23 can not be applied to model GFG -8215A.

(2) The functions of item 14, 15, 16, 17 and 23 can not be applied to GFG -8216A, and GFG -8250A.

(3) The funct ion of item 15, 16-2, 16-3, 17 and 23 can not be applied to GFG -8217A.

(4) The function of item 20 for GFG-8216A/8250A can be selected from front panel.

(5) The function of item 20 and 21 for GFG -8215A can be selected from front panel.

5. USAGE DESCRIPTION

These function generators can provide versatile waveforms of high efficiency and convenient operation. Familiarize yourselves with these functions thoroughly through Operation Manual and practice with all accurate operation procedures can lead you to easily master the performance of these Function Generators.

It is one of the best ways to observe waveforms by connecting the instruments to Oscilloscope. Watch the effect in different control of waveforms through Oscilloscope carefully when proceeding the follow ing steps:

5 -1.First-step check:

(1) Ensure that the voltage of the main supply is compatible with this instrument. The label on the rear panel states the required AC voltage.

(2) Connect the instrument to the main supply using the power cord supplied.

(3) Press PWR switch ¹ and ensure all the rotary controls are pushed in, then rotate AMPL ¹² knob to make the indication point up forward.

(4) Rotate the FREQ ¹³ control fully anticlockwise.

5 -2.Triangle, square and sine wave

(1) First select Function ⁸ , and select Range ⁷ , rotate FREQ ¹³ , to set the required frequency.(read out from display window).

(2) At this moment, connect Output ²² , to oscilloscope for observing output signal, or connect to other experiment circuit.

(3) Rotate AMPL ^{1 2} again to control waveform amplitude.

(4) If attenuation output signal is required, pull out AMPL ¹² knob to obtain 20dB attenuation or press (12a) knob for additional 20dB attenuation..

(5) The phase-relation of Output Waveform shown in Figure 1 as below:

l Figure 1.

5 -3.Pulse wave generation

(1) First press the key ( ) of Function ⁸ ; then select Range ⁷ , and rotate FREQ ¹³ , to set required frequency range.

(2) Connect output-terminal ²² to oscilloscope for observing output signal.

(3) Pull out and rotate Duty ‰ to adjust the width of pulse waveform.

(4) Adjust AMPL ^{1 2} knob to control pulse amplitude.

(5) Pull out AMPL ¹² knob to get 20dB attenuation of output.

5 -4.Ramp wave generation

(1) First press the key ( ) of Function ⁸ , then select Range ⁷ , rotate FEEQ ^{1 3} switch to set required frequency range.

(2).Connect output-terminal ²² to oscilloscope for observing output signal.

(3) Pull out and rotate DUTY‰ to adjust the slope of ramp waveform.

(4).Adjust AMPL ^{1 2} knob to control output amplitude of ramp waveform.

(5).Pull out AMPL ¹² knob to obtain 20dB attenuation of output.

5 -5.TTL/CMOS signal output

(1) First select Range ⁷ , rotate FREQ ^{1 3} to set required frequency range.

(2) Connect BNC connector of TTL/CMOS ²⁰ to oscilloscope or to other experiment circuit for observing output signal.

(3) At this moment, output is square waveform fixing to TTL level; suits for general TTL integrated circuit.

(4) If square waveform of CMOS level is required, can pull out CMOS

10 knob to adjust voltage level.

5 -6.Variation of external voltage-controlled frequency

This mode of operation allows the user to adjust the frequency of the function generator with an external DC control Voltage. It also provides an easy way for your adjustment.

(1) Select Function ⁸ first, then select Range ⁷ , rotate FREQ ¹³ t o set required frequency range.

(2) Connect external control voltage (0 ± 10V) to the VCF ²¹ connector via a suitable lead, and generate signal from Output ²² .

(3) Other adjustments, such as AMPL ¹² switch can change amplitude of signal, or get attenuation; adjust Offset ¹¹ for DC level, rotate Duty

‰ switch can change output signal of pulse or ramp waveform etc..

5 -7.Auto Sweep

(1) First select the required waveform by pressing Function ⁸ button, then select required frequency range by pressing range ⁷ push button.

(2) Connect output terminal ²² to oscilloscope for observing output signal.

(3) Rotate frequency ¹³ to determine the upper limit frequency.

(4) Pull out frequency ¹³ to perform auto-sweep operation.

(5) Rotate SWEEP/TIME ¹⁴ and SWEEP/RATE ¹⁶ to adjust sweep time and rate.

(6) Pull out (press) LIN/LOG ¹⁴ to obtain LOG (LIN) sweep mode.

Note: The sweep width can only be adjusted during the sweep cycle and it can not be sto pped.

5 -8.AM/FM operation

(1) Select function ⁸ first; then select Range ⁷ , rotate FREQ ¹³ to set required frequency range.

(2) Connect output terminal ²² to oscilloscope for observing output signal.

(3) Press MOD ¹⁵ and pull out (press) MOD ^{1 6} to obtain FM/AM modulation mode.

(4) Adjust MOD ¹⁶ to achieve required modulation ratio.

5 -9. Precaution item

(1) Adjust DC OFFSET, will provide to change voltage of ± 10V (no load) or ± 5V (50Ω load). However, signal added DC level, is still limited to ±20V (no load) or ± 10V (50Ω load). In case of over-voltage, clip will appear as shown in Figure 2:

(2) Output connector label 50Ω, indicated that signal source impedance is 50Ω. Connect to any of impedance circuit, but output voltage and terminal impedance will be rated. To avoid oscillation, terminal shall be connected to 50Ω (When using high frequency and square output), and its connecting line shall be as short as possible.

(3) When adjust Duty knob to leftward position, the ratio of positive state

to negative state, expand to not less than 80:20. It can expand Square

wave to Pulse wave, expand Triangle wave to Ramp wave and Sine

wave to unsymmetrical Sine wave. As shown in Figure 3 is for

adjustment of Duty control to obtain required waveform.

l Figure 2.

l Figure 3.

6. APPLICATION NOTE

This section describes the application of the Function Generators in details as well as a brief description relating to the block diagram. Only for the essent ial application method.

(A) Trouble-shooting using signal -tracing method.

This method is similar to signal replacing way. The signal of model will be fixedly sent to input terminal. Observing its signal wave on the oscilloscope from front stage to rear stage orderly until appear a signal with normal input but with abnormal output.

(B) Use as bias source and signal source circuit.

Utilize the Figure 4 of connecting type, which can provide bias of a transistor and signal input. The output waveform can be observed from oscilloscope. Adjust to the best condition with output max. amplitude and no distortion. Adjust DC OFFSET to see the different effect of different bias condition.

(C) Amplifier over -load characteristics

The Sine wave input will be different from output the overload point.

Using Triangle wave will easily observe the display of oscilloscope. It

can decide the linear range of output waveform. And the largest

no-distortion output amplitude.

(D) Using the Square wave test the characteristics of amplifier circuit.

It can’t actually explain the transient response of amplifier by using Sine wave for the frequency response curve observation,. but using the high order poly -wave, Square wave, instead to display its waveform from the oscilloscope can show up many characteristics of amplifier.

(a) Using the circuit of figure 5, the 50 Ω connector trim the oscillation effect of Square wave.

(b) Use the output of Triangle wave, adjust the amplitude until there are no clipping happened in the applied frequency.

(c) Select Square wave, adjust frequency, choose to watch the wave-form of middle of amplifier pass band, like 20Hz, 1kHz, 10kHz and etc.

(d) The output waveform of (c), must get something with frequency Figure 6 shows some possible conditions.

CAUTION: The composed poly-wave frequency of Square wave is quite large, so it’s not suitable for the narrow band amplifier testing.

(E) Test of logic circuit

This equipment is suitable for logic circuit testing. Using Square or Pulse wave can analyze or watch the frequency waveform of a designed testing circuit. Also the DC Offset effect, drive the plug-in model board or logic circuit trouble-shooting and etc. Used as signal tracing and signal replacing operation:

(a) Connect the lines as Figure 7.

(b) According to the operation guide in this manual, set Square wave or Pulse wave output.

(c) Use the label TTL, CMOS output terminal testing TTL logic circuit.

(d) To test CMOS circuit by pulling up the switch of TTL/CMOS, and adjust CMOS level by rotating the switch to set the proper level (e) Use dual-trace scope to show the input-output timing relation

judged by the two waves shown in Figure 4.

(F)Testing of speaking and impedance network

This equipment can be used to test the frequency characteristics of speaker or any impedance network. It also can get the resonant frequency of network.

(a) Connect the device under test as in Figure 8, can use oscilloscope in stead of voltmeter.

(b) When use voltmeter, adjust the frequency of instrument record down voltage relative to frequency.

(c) When testing speaker, if there is a peak volt value, when in low freq., this must be the resonant fr eq. of this speaker, see Figure 10.

Whether installation may cause any effect to this frequency or not?

The proper design of case-installation will cause two small ramps on both sides of this sharp ramp.

(d) In testing other impedance network, the resonant may not occur in

low frequency. But in approaching the resonant frequency, there

are still increasing in voltage, then the impedance can be tested as

following:

(1) Series connect a R1 to the network under test as in Figure 9.

(2) Get voltage read out in E1, E2, adjust R1 until E2 is equal to one half of E1.

(3) Under this frequency, the impedance network is the same as the R1.

(G)Act as automatic test of speaker

Because there provide the auto feature in this equipment, the output can drive to amplifier for testing the frequency response of speaker.

(a) Set Auto/Manual to Auto position.

(b) Set function to Sine wave (c) Set Range to 20kHz

(d) Sweep mode (LIN, LOG), sweep width, sweep time can be set in any value.

(e) The line connected is showed in Figure 11.

l FIGURE 4

l FIGURE 5 l FIGURE 6

l FIGURE 7

l FIGURE 8

l FIGURE 9

l FIGURE 10

l FIGURE 11 7. MAINTENANCE

The following instructions are used by qualified person only to avoid electrical shock, do not perform any service other than contained in the operation instructions unless you are qualified to do so.

7-1.Fuse Rating and type

If the fuse blows, the FUNCTION GENERATOR will not operate. Try to determine and correct the cause of the blown fuse, then replace the fuse with correct rating and type shown as below:

FUSE Rating and Type Rating Input MODEL

115V 230V Watts VA

GFG-8215A T0.315A 250V T0.16A 250V 22 28 GFG-8216A T0.315A 250V T0.16A 250V 25 32 GFG-8217A T0.315A 250V T0.16A 250V 27 34 GFG-8219A T0.315A 250V T0.16A 250V 29 36 GFG-8250A T0.315A 250V T0.16A 250V 25 32 GFG-8255A T0.315A 250V T0.16A 250V 29 36

WARNING: For continued fire protection, replace only

with 250V fuse of the specified type and rating, and

disconnect the power cord before proceeding fuse

replacement.

7 -2.Fuse Replacement Procedure

When you proceed calibration or maintenance of the Function Generators, if you want to replace the fuse, the upper cover must be removed according to the following steps:

1).The handle must be turned downward 90 degrees first.

2).Pull apart the handle from the Function Generator. Please turn the handle left and right side slightly, that will make easier to pull off the handle.

3).There are two washers inside of two holes (the joints of handle and case)

respectively. Please use a screwdriver to pry open these washers.

4).Please use a screwdriver to open the screw located at upper side of rear panel. Therefore, the upper cover can pull toward the backside. In the meantime, the upper cover is moved.

Note: If you want to install the upper cover, please reverse above steps.

7 -3. Cleaning

To keep the instrument clean, wipe the case with a damp cloth and

detergent. Do not use abrasives or solvents.